1. Field
Embodiments of the present invention relate to an optical transceiver implemented with both of an optical transmitter and an optical receiver, and particularly to an optical transceiver with a tunable optical transmitter for the WDM optical communication system.
2. Related Background Art
The Wavelength Division Multiplexing (WDM) optical communication system has been practical. One standard of the dense WDM (DWDM) communication system, which is one of the WDM standard, rules 100 grid wavelengths with a span of 50 GHz in the 1550 nm range (i.e. a frequency range of 192 THz-197 THz). A large sized optical signal source, such as transponder, has been conventionally applied to the DWDM system. The optical signal source, which typically installs a semiconductor laser diode (hereinafter denoted as “LD”), requires a precise temperature control for the LD.